SYNTHESIS AND CHARACTERIZATION FOR VARIOUS BIOLOGICAL ACTIVITIES OF TRANSITION METAL COMPLEXES OF QUERCETIN

Flavonoids are a group of polyphenolic compounds with multiple biological activities including antioxidant, anti-inflammatory and anti-cancer activities. The reduced bioavailability of flavonoids, however calls for structural modifications. Quercetin possesses multiple hydroxyl groups and an ability to chelate metal ions. Transition metal complexes have shown therapeutic promises in treatment of both inflammation and cancer. The present work describes synthesis of transition metal complexes of quercetin which resulted in the synthesis of the complexes of the type M2L which were characterized by IR and proton NMR. Although anti-oxidant and anti-inflammatory activity of the quercetin-Cu complex was higher than quercetin, the anticancer activity of the quercetin-Zn complex was much higher. A mechanism of action for the same is proposed.